There are many palces. Just on Cornelia Street:
Le Gigot
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Blue Ribbon Bakery

Unfortunately there are no quiet places on Bleecker. Where exactly is the recital, NYU is a sprawling.

how about Gonzo on W.12th? go to www.menupages.com and check out the menu first.

I have a friend in Manhattan, who really likes Le Gigot mentioned by Auduchamp1. I haven't been there personally, but it worth a try. ITA with menupages.com, a great resource.

Gonzo is one of my favorite neighborhood restaurants (I live 2 blocks away) but it is VERY noisy when more than 3 tables are full.

All of aduchamp's suggestions are good restaurants, but kind of small for a large group . . .

Looks like the snowstorm is going to pass us by - a couple of inches late tonight and then sleety rain all day tomorrow is predicted . . . looks like OP's original plans of North Square will have to do - not a bad choice, anyway.